Center-punch



HMM/MIM /f/M NA PETERS, PHDYO LITHOGRAPH UNITED STATES PATENT OEEicEo MILTON BOWKER, OF FITCHBURG, ASSIGNOR TO VARREN N. ABBOTT, OF BOSTON, MASSACHUSETTS.

CENTER-PUNCH.

Specification forming part of Letters Patent No. 50,442, dated October 17, 1865.

To all whom it may concern:

Be it known that I, MILTON BOWKER, of Fitchburg, in the county of Worcester and State of Massachusetts, have invented a new and useful or Improved Apparatus for Centering a Shaft or Article to be Turned in aLathe; and I do hereby declare the same to be fully described in the 'following specication and represented in the accompanying drawings, of which- Figure l is a top view, Fig. 2, a horizontal section, taken longitudinally 5 Fig. 3, a longiverse and vertical section.

In the said drawings, A A are two levers, which arejointed together at one end of each, the joint being shown at a. These levers have two springs, b b, applied to them for the purpose of opening them apart, the arrangement otl such springs being as shown in the drawings. To the middle of each of the said levers a recessed or V-shaped jaw, B, is jointed, the joint or connection being shown at c. Ahove the said jaws, and midway of them, is a tubular punch-carrier, C, which, at or near its foot, is connected or jointed to two toggles, D D, which, in turn, are jointed to the middles of the arms E E. These arms at their lower ends are jointed to the two jaws, while at theirupper ends they are similarly jointed to aslider or annulus, F, which encompasses and slides freely on the punch-carrier.

A punch, g, is arranged within the carrier F, and is provided with an elevating-spring, H, overriding it and being arranged between the upper end of the carrier and lan annulus,

d, lixed on the upper end of the punch. A shoulder, e, formed on the lower part ot' the punch, serves to limit the elevation ofthe punch by the spring. The lower end of thepunch is to be conical in form.

When any cylindrical sh aft or piece ot' metal is placed between the jaws Iand they are closed on its curved surface, they will so adjust the said piece of metal that its axis will be in the prolongation of that ot' the punch, the said punch, by the peculiar action of the two levers l A A and the mechanism for guiding it and contudinal and vertical section, and Fig. 4 a transnectng it with the jaws, heilig caused under any movement ofthe jaws, either away from or toward each other, to be centralized relatively to them, or to have its axis preserved in a line which, when extended, will always pass midway between the jaws. On striking with a hammer on the head of the punch such punch may be driven down upon an article grasped by the jaws, and will duly center the end of the article or make a correct depression in the center or' such end.

The improved shaft-centering apparatus as composed of the levers A A, the recessed jaws B B, the punch g, the punch-carrier C, the arms E E, the toggles D D, and the slider F, arranged and jointed or applied together substantially in the manner and so as to operate as specified.

MILTON BOWKER.

Witnesess R. H. EDDY, F. P. HALE, Jr. 

